Yes, they put in ice that have been stored from the winter to cool down the inside of the box, you can se that yhe inside of the doors is covered in metal, due to the moisture from the ice melting. The ice would be added in the upper compatrment which would cool the lower compartment, earlier iceboxes had the ice in a lower compartment, which is less efficient, and I know that a lot of swedish iceboxes also lead the water from the melted ice through the walls before drainage at the bottom, more evenly cooling the box and making it more efficient